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<div class="titlepage"><div><div><h5 class="title">
<a name="spirit.lex.reference.lexer_concepts.narylexer"></a><a class="link" href="narylexer.html" title="NaryLexer">NaryLexer</a>
</h5></div></div></div>
<h6>
<a name="spirit.lex.reference.lexer_concepts.narylexer.h0"></a>
            <span class="phrase"><a name="spirit.lex.reference.lexer_concepts.narylexer.description"></a></span><a class="link" href="narylexer.html#spirit.lex.reference.lexer_concepts.narylexer.description">Description</a>
          </h6>
<p>
            <span class="emphasis"><em>NaryLexer</em></span> is a composite lexer component that has
            one or more subjects. The NaryLexer allows its subjects to be treated
            in the same way as a single instance of a <a class="link" href="lexer.html" title="Lexer"><code class="computeroutput"><span class="identifier">Lexer</span></code></a> following the Composite
            Design Pattern.
          </p>
<h6>
<a name="spirit.lex.reference.lexer_concepts.narylexer.h1"></a>
            <span class="phrase"><a name="spirit.lex.reference.lexer_concepts.narylexer.refinement_of"></a></span><a class="link" href="narylexer.html#spirit.lex.reference.lexer_concepts.narylexer.refinement_of">Refinement
            of</a>
          </h6>
<div class="blockquote"><blockquote class="blockquote"><p>
              <a class="link" href="lexer.html" title="Lexer"><code class="computeroutput"><span class="identifier">Lexer</span></code></a>
            </p></blockquote></div>
<div class="variablelist">
<p class="title"><b>Notation</b></p>
<dl class="variablelist">
<dt><span class="term"><code class="computeroutput"><span class="identifier">l</span></code></span></dt>
<dd><p>
                  A NaryLexer.
                </p></dd>
<dt><span class="term"><code class="computeroutput"><span class="identifier">L</span></code></span></dt>
<dd><p>
                  A NaryLexer type.
                </p></dd>
</dl>
</div>
<h6>
<a name="spirit.lex.reference.lexer_concepts.narylexer.h2"></a>
            <span class="phrase"><a name="spirit.lex.reference.lexer_concepts.narylexer.valid_expressions"></a></span><a class="link" href="narylexer.html#spirit.lex.reference.lexer_concepts.narylexer.valid_expressions">Valid
            Expressions</a>
          </h6>
<p>
            In addition to the requirements defined in <a class="link" href="lexer.html" title="Lexer"><code class="computeroutput"><span class="identifier">Lexer</span></code></a>, for any NaryLexer the
            following must be met:
          </p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                    <p>
                      Expression
                    </p>
                  </th>
<th>
                    <p>
                      Semantics
                    </p>
                  </th>
<th>
                    <p>
                      Return type
                    </p>
                  </th>
</tr></thead>
<tbody><tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">l</span><span class="special">.</span><span class="identifier">elements</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      The tuple of elements.
                    </p>
                  </td>
<td>
                    <p>
                      A <a href="../../../../../../../../libs/fusion/doc/html/index.html" target="_top">Boost.Fusion</a>
                      Sequence of <a class="link" href="lexer.html" title="Lexer"><code class="computeroutput"><span class="identifier">Lexer</span></code></a> types.
                    </p>
                  </td>
</tr></tbody>
</table></div>
<h6>
<a name="spirit.lex.reference.lexer_concepts.narylexer.h3"></a>
            <span class="phrase"><a name="spirit.lex.reference.lexer_concepts.narylexer.type_expressions"></a></span><a class="link" href="narylexer.html#spirit.lex.reference.lexer_concepts.narylexer.type_expressions">Type
            Expressions</a>
          </h6>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                    <p>
                      Expression
                    </p>
                  </th>
<th>
                    <p>
                      Description
                    </p>
                  </th>
</tr></thead>
<tbody>
<tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">l</span><span class="special">.</span><span class="identifier">elements_type</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      Elements tuple type.
                    </p>
                  </td>
</tr>
<tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_nary_lexer</span><span class="special">&lt;</span><span class="identifier">L</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      Metafunction that evaluates to <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">true_</span></code>
                      if a certain type, <code class="computeroutput"><span class="identifier">L</span></code>
                      is a NaryLexer, <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">false_</span></code>
                      otherwise (See <a href="../../../../../../../../libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL
                      Boolean Constant</a>).
                    </p>
                  </td>
</tr>
</tbody>
</table></div>
<h6>
<a name="spirit.lex.reference.lexer_concepts.narylexer.h4"></a>
            <span class="phrase"><a name="spirit.lex.reference.lexer_concepts.narylexer.invariants"></a></span><a class="link" href="narylexer.html#spirit.lex.reference.lexer_concepts.narylexer.invariants">Invariants</a>
          </h6>
<p>
            For each element, <code class="computeroutput"><span class="identifier">E</span></code>,
            in any NaryLexer, <code class="computeroutput"><span class="identifier">L</span></code>,
            the following invariant always holds:
          </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
                <code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_lexer</span><span class="special">&lt;</span><span class="identifier">E</span><span class="special">&gt;::</span><span class="identifier">type</span></code> evaluates to <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">true_</span></code>
              </li></ul></div>
<h6>
<a name="spirit.lex.reference.lexer_concepts.narylexer.h5"></a>
            <span class="phrase"><a name="spirit.lex.reference.lexer_concepts.narylexer.models"></a></span><a class="link" href="narylexer.html#spirit.lex.reference.lexer_concepts.narylexer.models">Models</a>
          </h6>
<p>
            The following lexer components conform to this model:
          </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
                lexer sequence component
              </li></ul></div>
<p>
            <span class="bold"><strong>FIXME</strong></span> Add more links to models of NaryLexer
            concept
          </p>
</div>
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<td align="right"><div class="copyright-footer">Copyright © 2001-2011 Joel de Guzman, Hartmut Kaiser<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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